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Discussion Starter #1
Hello every body,

I would like to ask if anybody has had a SAAB repair similar to what I am experiencing.


I have a 2003 SAAB 95 petrol automatic. The car has traveled about 175,000 kilometers.


The car had a problem with the transmission...both engine light and transmission warning lights came on, hard shifting between gears and it finally went into 'limp home mode'.


I took the SAAB to a SAAB garage. They said the problem was because of the transmission and proposed two solutions: replacing the solenoid assembly and replacing the whole transmission. Error code P0748. Both of these options were for brand new parts from SAAB in Sweden. I took the brand new transmission replacement option.


Here is a summary of what is happening....


  1. I picked up the SAAB after the new transmission was installed and after about 20 kilometers on the highway the initial problem came back, ie both warning light came on, hard shifting between gears and car went into 'limp home mode'. I took the car back to the garage.
  1. They diagnosed that the problem was because of a faulty solenoid assembly and then arranged for a new new replacement to be installed. Error code P0785
  2. After the replacement solenoid assembly had been installed they diagnosed that there was a problem with the TCM which they later went to say was not faulty
  3. I picked up the car (second time now) and after 51 kilometers the car had as the same problems as in the original instance, ie both warning lights on, hard shifting gears and in limp home mode. I toke the car back to the garage
  4. The garage is now saying the problem is due to a faulty TCM and they have installed a brand new TCM from Sweden. I am waiting on an update as to how this went.
They have confirmed that they tested all the connectors at the TCM and at the transmission. All parts installed are brand new.


Does any body have an opinion on the way the garage has approached this repair. Other than: transmission, TCM and connectors, what else is there left to replace? I have no reason to doubt their competence or their honesty. The garage is a big dealer ship and sells / services: land rover, volvo kia and other brands.

Thank you and regards


Robert
 

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There is lots of information on the forums regarding problems with the 5 speed AW gearbox but a common problem is sticking solenoids in the valve body giving the P07XX errors.Wiring to and from the TCM and indeed the TCM itself can also be the cause.

Generally for a DIY approach the order of things to do on the troubleshooting list is

1.Full ATF flush
2.Replace TCM
3.Replace valve body/upgrade solenoids
4.Replace gearbox.

From your description you say the gearbox was the first thing that was replaced.....which in my own opinion would be the wrong place to start.

There is also a theory that sticking solenoids cause the TCM to blow so if you had a faulty TCM/valve body problem at the start then replacing gearbox and valve body would have no real benefit until the TCM was replaced.

Begs the question is the car now ok after the finally replacing the TCM.

The bill must be telephone numbers by now I should think!
 

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Your mechanic put a new gearbox in when you didn't need one, that's the bottom line.

the P0748 code (and a couple of others) are entirely electrical, the code says that the solenoid is either shorted, open or the TCM is shorted/open. Most everyone who has ever come here with this code and the others finds that the issue is the TCM.

The diagnostic, which BTW is described in the WIS, is to measure the resistance of the solenoid in the transmission. If it is within spec the TCM is definitely the issue.

Edit: you can measure this resistance from the connector where the TCM plugs in, you do not have to take anything apart on the transmission.

So the end result is that you paid for a new transmission and the labor to put it in when you needed a (used) TCM that would have cost you roughly $100 and a 5-mintue install time.

As CJ said there is some speculation that the root cause of the TCM failures is stuck solenoids which cause the TCM to try to over-drive them and then fail. But I've also seen instances where used TCM's were installed in cars with these faults and they work for a long time. (however those owners also changed the oil with a full 3x drain/flush so that may have eliminated the sticking)

I would not hesitate to go back to your mechanic and raise a huge issue. They diagnosed the problem wrong, did not really understand the code that was given to them and cost you a good bit of money. I'd be asking that they cover the transmission and its installation for FREE (or tell them that they can put the old one back if they like) as a starting point. You should be at least able to get them to cover the labor and sell you the transmission at their cost, which is still probably a big amount.
 

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Miltie is correct. And TCM stands for "transmission control module". Search on this forum and you will see many such problems solved with this simple and cheap fix.
 

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the posters have . I believe really summarized the situation. I would add that in the past few months Aisin have come up with a maintenance policy for this transmission that says the trans oil should be changed every 40,000 miles, roughly 70,000 km. GM say its a lifetime fill. Morons.

I have done my changes the DIY way which while not ideal is better than doing nothing, which can lead to issues.

Doing a complete trans flush and fluid replacement with the Tech 2 and a flush machine is a better deal. There is no conventional trans oil pan with filter as found in truck style transmissions. The trans is split vertically; the solenoids referred to have screens on them. I am told by the techs I use, that the process for flush includes a cycle where the tech 2 causes the solenoids to "vibrate" in the solvent flush process, thus causing any debris trapped in the solenoid screens to drop and be removed. This is a good deal but costs about $250.00 usd and uses 12 litres of fluid in the process along with the solvent used.

Finding a dealer with the appropriate machine and tech 2 that works with SAAB may be an ordeal. I cant imagine how difficult it would be in NZ. In Toronto there are three dealers that have the equipment, and at least two of them are totally complete rip off artists.

I would also add that for the OP, getting resolution is a very difficult task. Even though the techs and the shop totally dropped the ball and through sheer incompetence , plainly speaking, stole money from him. Scoundrels.
Grrrr.
Sad to say. What a Christmas....
 

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as I've said to people here in the past, I do a single drain-fill on my transmission oil every other oil change (which is about 12-15K miles total) so the oil is completely changed every 36-45K miles, but the oil is always clean and the car now has 190K on it.

the only issue I've ever had with the transmission was the P0785 (written extensively in this forum) and I went to a lot of trouble to finally figure out it was the TCM, which was my last suspect.

My point is that if you keep up with the maintenance it should last a long time.


And I'd still go after the shop for the wrong diagnosis. And if they are anything near honest they should sell you the transmission for what it cost them and give you the labor for free.
 

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as I've said to people here in the past, I do a single drain-fill on my transmission oil every other oil change (which is about 12-15K miles total) so the oil is completely changed every 36-45K miles, but the oil is always clean and the car now has 190K on it.

the only issue I've ever had with the transmission was the P0785 (written extensively in this forum) and I went to a lot of trouble to finally figure out it was the TCM, which was my last suspect.

My point is that if you keep up with the maintenance it should last a long time.


And I'd still go after the shop for the wrong diagnosis. And if they are anything near honest they should sell you the transmission for what it cost them and give you the labor for free.
^^^^ this.
 

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Discussion Starter #8
Thank you evrybody for all your replys. I appreciate the support and information.

Here is an update...I spoke to the mechanic yesterday. The new TCM had just been installed and he said that he had not experienced any problems. No fault codes and no problems after him driving about 150 kilometers. I did not accept my SAAB and I said that I would visit his garage on Monday.

I asked him why he did not discover the TCM had to be replaced earlier in the testing. He said that he did not find a fault code that would specifically isolate the TCM as a sole cause of the problem. He then said that he had contacted SAAB France and their techical person said that 'when you change a gearbox you should change the TCM at the same time'. His view was that the gear box was the problem and HE THEN HAD to replace the TCM as a consequence of installing a new gear box.

The car and me are in France.

I should have added that I changed the auto transmission oil only 2 weeks prior to the problem appearing and prior to that I changed the transmission oil about 70,000 kilometers before the recent oil change, ie transmission oil changes are well before the reccomended mileages.

Thank you all again for support. I have read up more about this on the forum. I now have a clearer understanding of the sequence for this type of repair.

I see a refund coming in my direction.

Thanks and regards

Robert
 

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I asked him why he did not discover the TCM had to be replaced earlier in the testing. He said that he did not find a fault code that would specifically isolate the TCM as a sole cause of the problem.
This is wrong. You said he was reading a P0748 code.

The P0748 code that he got is entirely electrical the WIS says this. It also says that you should test the solenoids by testing the resistance. This can be done before the transmission is removed. If he had tested the solenoid resistance he would have found they were within spec and that would have pointed him in a direction away from the transmission. (P0785 is also an entirely electrical code)


He then said that he had contacted SAAB France and their techical person said that 'when you change a gearbox you should change the TCM at the same time'. His view was that the gear box was the problem and HE THEN HAD to replace the TCM as a consequence of installing a new gear box.
This is also wrong. The TCM should be re-adapted to a new transmission after a gearbox change but this does not require replacement of the TCM. This too is in the WIS
 

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Perhaps a moot point but Saab does not exist anymore so I dont know who "Saab France" would be other than perhaps an Orio representative (they took over the parts business)

Fundementally if your workshop had followed the troubleshooting steps as outlined in the Saab WIS against the error code(s)then you should not have had a gearbox fitted.

Unfortunately for you it looks like they took the easy option and most expensive first by fitting a gearbox.

BTW if you can easily download the EPC and WIS over in the Tech2 forum and see the troubleshooting paths for the codes.
http://www.saabcentral.com/forums/showthread.php?t=622081
 

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Just a sad commentary on repair shops wherever.

Mais Oui. so nice to you.

Certainement. anything for you sir

Merde customer reaction in this case
lol
 

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Thank you evrybody for all your replys. I appreciate the support and information.

Here is an update...I spoke to the mechanic yesterday. The new TCM had just been installed and he said that he had not experienced any problems. No fault codes and no problems after him driving about 150 kilometers. I did not accept my SAAB and I said that I would visit his garage on Monday.

I asked him why he did not discover the TCM had to be replaced earlier in the testing. He said that he did not find a fault code that would specifically isolate the TCM as a sole cause of the problem. He then said that he had contacted SAAB France and their techical person said that 'when you change a gearbox you should change the TCM at the same time'. His view was that the gear box was the problem and HE THEN HAD to replace the TCM as a consequence of installing a new gear box.

The car and me are in France.

I should have added that I changed the auto transmission oil only 2 weeks prior to the problem appearing and prior to that I changed the transmission oil about 70,000 kilometers before the recent oil change, ie transmission oil changes are well before the reccomended mileages.

Thank you all again for support. I have read up more about this on the forum. I now have a clearer understanding of the sequence for this type of repair.

I see a refund coming in my direction.

Thanks and regards

Robert
TCM has to be programmed to the new gearbox not replaced... oh well. that probably set you back a good 6k
 

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TCM has to be programmed to the new gearbox not replaced... oh well. that probably set you back a good 6k
TCM's do not have to be programmed to the gearbox. They have to be adapted, but the only thing you might see if you don't do that is some flares or rough shifts but the transmission should work perfectly well.
 

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If the TCM is brand new it would likely need the firmware loading versus the VIN...so it would need Tech2 programming.
A used one however already has this done so would work by default.

This thread really demonstrates the value of the Saabcentral and indeed other forums.
Take a bit if interest in the car you are driving and the information is out there on the web.

Unfortunately for the OP he didnt do his homework until after the event..........and got well and truly boned,even if the shop in question
acted in good faith it was unprofessional at best.
 

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New TCM needs to marry with TECH2.
TCM has several versions of program (tex diesel has NO pedal changing gears).
 

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If the TCM is brand new it would likely need the firmware loading versus the VIN...so it would need Tech2 programming.
A used one however already has this done so would work by default.
that's something that I don't know since I've never put a new TCM into a car. I'm not sure anyone ever should


New TCM needs to marry with TECH2.
TCM has several versions of program (tex diesel has NO pedal changing gears).
from what I've seen the same firmware is in every TCM. There are two versions of the TCM one for cars with paddle shift and one for cars without since it's not only software but also hardware (a separate line to SID to get the shift signal)

Aisin could have changed that and used firmware to block the signal in later versions though. And of course there are upgraded firmwares that fix early problems with the control program.
 

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Nope.
TCM is same, but when you marry it with car TCM uses only certain sw.
I have tried this, my TiD. When I swap it to my brother's B235R, TCM uses paddles normally. And vice versa, when I returned it to my TiD, paddles are not useable anymore.
 
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